Fence Calculator
Calculate posts, panels and rails for any fence by linear feet, panel width and gate count.
The fence calculator returns posts, panels, rails and hardware for any wood or pre-built panel fence. Standard panels come in 6 ft and 8 ft widths - 8 ft is the dominant length for stockade and dog-ear privacy fences sold at home improvement stores. Posts space at one per panel plus one starter, plus an extra post for the latch side of every gate (gates need 4x4 or 6x6 posts on both sides for hinge strength). Use 2 rails for fences up to 4 ft tall, 3 rails for taller fences. For the exact concrete-per-post math (which depends on hole depth and post size), use the post hole concrete calculator.
Explore all our fencing calculator tools, or browse the full construction & home improvement diy calculators.
Frequently asked questions
With 8 ft panels: 13 sections, 14 posts (or 15 with one gate). With 6 ft panels: 17 sections, 18 posts. Always round panel count up - the last section can be a partial panel cut to fit. Add one extra post per gate because gates need solid posts on both sides for hinge and latch strength.
13 panels at 8 ft width or 17 panels at 6 ft width. Subtract one panel per gate (each gate replaces a section of panel with a gate frame). For a 100 ft fence with two gates, that is 11 panels of 8 ft, plus 2 gate frames, plus 16 posts (15 + 1 extra for the second gate latch side).
4x4 pressure-treated posts are standard for 6 ft privacy fences. Use 6x6 posts for 8 ft tall fences or any fence in high-wind regions. Post length should be fence height plus 2 ft below grade (8 ft posts for a 6 ft fence). Set posts in 10 inch diameter holes 30 inches deep with 6 inches of gravel below the concrete.
About 1.5 bags of 60lb concrete per post for a standard 4x4 in a 10 inch diameter, 30 inch deep hole. For 14 posts on a 100 ft fence that is 21 bags. The fence calculator gives a quick estimate; the post hole concrete calculator gives the exact number including post size displacement and your chosen bag size (40, 60 or 80 lb).
Pre-built panels are 30-50% faster to install and cost about the same as buying the lumber separately. Use pre-built for stockade and dog-ear privacy fences where the look is standard. Build on-site for custom heights (anything other than 4 or 6 ft), board-on-board patterns, horizontal-board modern fences and any time you need fence height to match a sloped yard step-by-step.